Radiation curable compositions containing carbon-carbon unsaturated monomers and polythiols were developed in the early 1970s. U.S. Pat. No. 4,234,676 (Hein et al.) describe a composition comprising a carbon-carbon unsaturated polymer, a crosslinkable monomer, a polythiol, and curing agent directed primarily at printing plate production.
U.S. Pat. No. 4,808,638 (Steinkraus, et al) describes a composition comprising a norbornene resin, polythiol, and free radical initiator that can be photocured in visible light when an iron arene complex is present.
U.S. Pat. No. 4,139,385 (Crivello) describes a composition comprising a polyolefin, polythiol, and onium salt photoinitiator. The films, 75 micrometers thick (3 mil), were curable by a cationic mechanism with UV light as an initiator.
U.S. Pat. No. 6,506,814 (Krongauz et al.) describes a UV curable insulating composition for electrical conductors comprising a UV or radiation curable (meth)acrylate oligomer, an acid functional adhesion promoter or thiol compound, a vinyl reactive diluent and a photoinitiator.